Final drive disconnect mechanism via transmission

ABSTRACT

A vehicle drivetrain for a vehicle including a transmission configured to move the vehicle with a surface engaging traction member and a final drive assembly configured to drive the surface engaging traction member. The final drive assembly includes a drive assembly coupler. A transmission coupler is operatively connected to the transmission and disposed between the transmission and the drive assembly coupler. The transmission coupler includes a first position engaged with the drive assembly coupler and a second position disengaged from the drive assembly coupler. An actuator is operatively connected to the transmission coupler and is configured to move the transmission coupler between the first position and the second position. The actuator, in one embodiment, includes a worm drive having a worm gear configured to move the transmission coupler along a longitudinal direction of the transmission. The worm gear rotates about an axis inclined with the longitudinal direction.

RELATED APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 15/976,949, filed May 11, 2018, having the title“Final Drive Disconnect Mechanism Via Transmission”, the disclosure ofwhich is expressly incorporated by reference in its entirety herein.This application also claims priority to United States ProvisionalPatent Application Ser. No. 62/507,420 entitled “Final Drive DisconnectMechanism Via Transmission” by Larry Boley et al., filed May 17, 2017,the disclosure of which is herein incorporated by reference in itsentirety.

FIELD OF THE DISCLOSURE

The present invention relates to a transmission or final drive assembly,and in particular, to a disconnect mechanism for a transmission or finaldrive assembly.

BACKGROUND

Tracked vehicles include a prime mover for producing power and atransmission assembly for receiving the power for transfer to adriveline or final drive assembly. The final drive assembly providespower to a sprocket or drive hub that drives the tracks along a surface.Instead of tracks, a vehicle may include wheels that receive the powerfrom the final drive assembly and operably move the vehicle along thesurface. In any case, the transmission output is connected to an inputof the final drive assembly.

At some point during vehicle operation it may be desirable or necessaryto maintain or service the transmission or final drive. To do so, it isoften necessary to remove the transmission or final drive from thevehicle. Before the transmission or final drive can be removed from thevehicle, however, the transmission output must be disconnected from theinput final drive assembly. Alternatively, the final drive assembly canbe completely removed, but this removal is often complex and requireslabor-intensive work.

In some military vehicles having a track, for example, an access port oropening is provided for a technician to access the transmission outputto disconnect the transmission output from the final drive assembly. Insome configurations while accessibility to the access port can berelatively straightforward, maintenance in the field can be difficultdue to the presence of mud, dirt, and other debris which can cover theaccess port. In other configurations, the design of the final driveassembly and sprocket for the track is such that there is limited or noaccess to disconnect a shaft. A separate port or access opening may berequired on the interior of the vehicle.

In some instances, the final drive assembly may need to be disconnectedfrom the vehicle before the transmission can be serviced. This againrequires a substantial amount of time and effort and is less desirablein applications where a “quick disconnect” feature is preferred.

Thus, a need exists for providing a means for disconnecting atransmission output from a final drive assembly. Moreover, it is furtherdesirable to design a disconnect mechanism for removably coupling atransmission output to a final drive.

SUMMARY

In one embodiment of the present disclosure, there is provided a vehicledrivetrain including a transmission configured to move a vehicle with asurface engaging traction member. The vehicle drivetrain includes afinal drive assembly configured to drive the surface engaging tractionmember wherein the final drive assembly includes a drive assemblycoupler. A transmission coupler is movably coupled to the transmissionand is disposed between the transmission and the drive assembly coupler,wherein the transmission coupler includes a first position engaged withthe drive assembly coupler and a second position disengaged from thedrive assembly coupler. An actuator is operatively connected to thetransmission coupler and is configured to move the transmission couplerbetween the first position and the second position.

In another embodiment, there is provided a method for disconnecting andconnecting a transmission drive element of a transmission from a finaldrive assembly. The method includes: moving a transmission connectoraway from the transmission and toward the final drive assembly to engagea drive assembly connector with the transmission drive element; anddisengaging the transmission connector from the drive assembly coupler,wherein the transmission connector moves away from the drive assemblycoupler for the disengaging the transmission drive element from thefinal drive assembly.

In still another embodiment, there is provided a vehicle comprising atransmission, including a transmission drive element, wherein thetransmission is configured to move the vehicle with a surface engagingtraction member. The vehicle drivetrain includes a final drive assemblyconfigured to drive the surface engaging traction member and atransmission coupler. The transmission coupler is coupled to thetransmission and is disposed between the transmission and the finaldrive assembly, wherein the transmission coupler includes a firstposition engaged with the final drive assembly and a second positiondisengaged from the final drive assembly. An actuator is operativelyconnected to the transmission coupler and is configured to move thetransmission coupler between the first position and the second position.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned aspects of the present invention and the manner ofobtaining them will become more apparent and the invention itself willbe better understood by reference to the following description of theembodiments of the invention, taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 illustrates a schematic depiction of a transmission assemblyincluding a transmission output portion configured to couple to a finaldrive assembly.

FIG. 2 illustrates a connect/disconnect mechanism of a transmission forconnecting to and disconnecting from a final drive assembly in adisconnected condition.

FIG. 3 illustrates a connect/disconnect mechanism of a transmission forconnecting to and disconnecting from a final drive assembly in aconnected condition.

FIG. 4 illustrates a transmission housing adapted to cover aconnect/disconnect mechanism of a transmission.

FIG. 5 illustrates another embodiment of a connect/disconnect mechanismof a transmission for connecting to and disconnecting from a final driveassembly in a disconnected condition.

FIG. 6 illustrates another embodiment of a connect/disconnect mechanismof a transmission for connecting to and disconnecting from a final driveassembly in a disconnected condition.

FIG. 7 illustrates another embodiment of a connect/disconnect mechanismof a transmission for connecting to and disconnecting from a final driveassembly in a connected condition.

FIG. 8 illustrates an end view of a connected/disconnect mechanism of atransmission.

FIGS. 9 and 10 illustrate a perspective end view of a connect/disconnectmechanism of a transmission.

Corresponding reference numerals are used to indicate correspondingparts throughout the several views.

DETAILED DESCRIPTION

The embodiments of the present invention described below are notintended to be exhaustive or to limit the invention to the precise formsdisclosed in the following detailed description. Rather, the embodimentsare chosen and described so that others skilled in the art mayappreciate and understand the principles and practices of the presentinvention.

In a general sense, the present disclosure relates to the control oftorque transfer from one member to another. In one condition, a firstmember and a second member can be coupled to one another such thattorque can be transferred therebetween, and in a second condition thefirst and second members can be decoupled from one another such thattorque cannot be transferred therebetween. While this disclosureprovides different examples of this control in a vehicular application,the disclosure is not intended to be limited to this application. Oneskilled in the art will appreciate varying aspects of the presentdisclosure outside of the vehicular application provided herein.

With reference to FIG. 1, a first illustrated embodiment includes aportion of a vehicle or machine 100. The vehicle or machine 100 can beany on-highway or off-highway vehicle or machine. The machine 100 can beused as an agricultural, construction, forestry, military or other typeof vehicle or machine. In FIG. 1, the machine 100 can include atransmission assembly 102 that can receive power from a power-generatingmechanism such as a prime mover, engine, motor, etc. The transmissionassembly 102 can transfer power or torque to a surface engaging trackingmechanism via a driveline, final drive assembly, or other means. Thesurface engaging traction member includes, but is not limited to awheel, a track, or a ski, each of which is configured to engage asurface including one or more of ground, soil, pavement, vegetation, androck.

The transmission assembly 102 of FIG. 1 includes an output portion 118that can be coupled to an input portion 120 of a final drive assembly108. The output portion 118 can be mechanically coupled to the inputportion 120 via a gearing and shaft arrangement. For instance, thetransmission assembly 102 can include a first shaft (not shown) disposedin the output portion 118. The first shaft can include a gear orsprocket (not shown) that can transfer torque to a second shaft (notshown) disposed in the input portion 120 of the final drive assembly108.

The final drive assembly 108 can also include an output (not shown) thatdrives a first drive track 112 on a first side 104 of the vehicle ormachine 100. The output can be rotatably coupled to a track sprocket(not shown) that drives the first drive track 112. Similarly, thevehicle or machine 100 can include a second drive track 114 disposed ona second side 106 thereof for moving the vehicle or machine 100 along aground surface. In FIG. 1, the first drive track 112 can be powered bythe first final drive assembly 108 and the second drive track 114 can bepowered by a second final drive assembly 110. In this manner, the firstdrive track 112 and second drive track 114 form the ground-engagingmechanism of the vehicle or machine 100. As previously described,however, other vehicles or machines may include one or more wheels asthe ground-engaging mechanism. Moreover, a different vehicle or machinemay include additional drive tracks or a combination of wheels and drivetracks as ground-engaging mechanisms.

As described above, many conventional vehicles or machines require thetransmission assembly to be disassembled or disconnected from the finaldrive assembly before the transmission assembly can be serviced. In someinstances, the entire transmission assembly needs to be removed from thevehicle or machine. To do so, the output of the transmission isdisconnected from the input of the final drive assembly. In someconventional arrangements, there is sufficient room to access theconnection between the transmission assembly and final drive assembly tomechanically disconnect the two assemblies from one another. Forexample, a shaft that connects the output of the transmission assemblyto the input of the final drive assembly can be removed withoutexcessive effort. However, in other instances including that of FIG. 1,there is little to no room to access the connection between the outputof the transmission assembly and the input of the final drive assembly.

In FIG. 1, for example, the first drive track 112 is driven by a tracksprocket (not shown). The track sprocket is driven by an output (notshown) of the final drive assembly 108. An area or region 116 betweenthe first drive track 112, and most notably its track sprocket, and thefinal drive assembly 108 can be extremely limited, thereby making itdifficult, if not nearly impossible, to access the connection betweenthe final drive assembly 108 and the transmission assembly 102. Inaddition, a connection location between the output portion 118 to theinput portion 120 of a final drive assembly 108 is also one in whichprovides little extra room to connect or to disconnect the transmission102 from the final drive assembly 108.

The transmission 102 of the present disclosure includes aconnect/disconnect mechanism or transmission coupler 130 which providesfor connection and disconnection of the transmission 102 to and from thefinal drive assembly 108 as further illustrated in FIG. 2. FIG. 2illustrates approximately one-half of the transmission 102 shown by aline 132. In addition, while FIG. 2 also illustrates one side of thetransmission 102, a similar connect/disconnect mechanism (not shown) isprovided at another side 134 of the transmission 102 of FIG. 1. Themechanism 130 is fixedly coupled to the transmission 102 at a flange orcollar 136 which is coupled to the transmission with connectors 138, oneof which is shown. The collar 136 is configured to locate the mechanism130 for alignment with the final drive assembly 108, which includes oneor more connectors 140 having one or more engagement structures such assplines 142 configured to engage the mechanism 130.

The mechanism or transmission coupler 130 includes an actuator 144located between the flange 136 and a plate 146. The plate 146 isoperatively connected to a movable connector 148 which moves along adirection 150, which engages with the connector 140. The moveableconnector 148 includes one or more engagement structures such as splines152 configured to engage the splines 142. The movable connector 148moves along a transmission support or transmission output shaft 153.Once connected, the transmission output shaft 153, also known as thetransmission drive element, is engaged with the final drive assembly 108to move the first drive track 112. The plate 146 defines a generallycircular perimeter, such that the plate 146 surrounds the end of thetransmission 102. In other embodiments, the plate is other thancircular. As described above, FIG. 2 illustrates one-half of the of thetransmission 102, such that the movable connector is circumferentialabout the transmission output shaft 153 and is configured as a couplingshaft.

The actuator 144, in one embodiment, includes a worm drive mechanism 154including an actuator 156 configured to drive an output shaft 158. Inone embodiment, the actuator includes a shaft operatively connected tothe output shaft. The output shaft 158 is moved in the direction 150 byrotation of the actuator 156 in either a clockwise or counterclockwisedirection. In one rotational direction, the plate 146 and the movableconnector 148 are moved toward the final drive mechanism 108 to engagethe splines 152 with the splines 142. In the opposite rotationaldirection, the movable connector is moved away from the final drivemechanism to disengage the splines 152 from the splines 142. In oneembodiment, the worm drive mechanism 154 include a worm gear and a wormscrew.

The flange 136 includes one or more channels configured to receive oneor more connectors 160 which fix the worm drive mechanism 154 to theflange 136. The flange 136 further includes a shaft channel 162configured to receive the output shaft 158 as it moves away from andtoward the flange 136 during movement of the output shaft 158 along thedirection 150.

In one embodiment, the actuator 156 is substantially perpendicular tothe output shaft 158 to provide access to a knob 164 of the actuator. Inthis configuration, the actuator 144 requires a minimal amount of space,thereby enabling engagement and disengagement of the transmission outputwith the final drive assembly 108. In other embodiments, the actuator156 is inclined with respect to the direction of movement 150.

The plate 146 includes an aperture 166 configured to accept an end 167of the output shaft 158 which is fixedly connected to the plate 146 toadjust movement of the plate 146 and consequently the moveable connector148 in both directions along direction 150. The plate 146 furtherincludes a channel 168 which extends through the plate and whichreceives a shaft or rod 170 including an end 172 fixedly connected tothe flange 136. The channel 168 includes an interior surface slightlylarger than an exterior surface of the shaft 170 such that the plate 146slides along the shaft 170 during movement of the plate 146 toward andaway from the splines 142 of the connector 140. While one shaft 170 isillustrated in FIG. 2, in other embodiments, one or more shafts arelocated in corresponding channels defined in the plate 146, whichgenerally includes a circular perimeter.

The plate 146 includes a centrally located aperture 174 (See FIG. 4)which surrounds the transmission output. The aperture 174 is defined bya rim 176 which is fixedly attached to the moveable connector 148. Asthe plate 146 moves along the direction 150, the interface between therim 176 and the connector 148 either pushes or pulls the connector 148into and out of engagement with the connector 142.

FIG. 3 illustrates the connection of the transmission 102 with the finaldrive assembly 108 resulting from a connection of the moveable connector148 with the connector 140. In this position, the splines 152 areengaged with the spline 142 such that rotation of output of thetransmission 102 drives the drive assembly 108 and consequently, thedrive track 112. In this embodiment, rotation of the actuator 156 hasmoved the plate 146 along the shaft 170 such that the transmissionoutput is locked with the final drive assembly 108. An opposite rotationof the actuator 156 moves the moveable connector 148 away from theconnector 140 to disengage the splines 152 from the splines 142.

FIG. 4 illustrates a perspective view of one end of the transmission 102including a partial view of the flange 136 and the plate 146 disposedadjacently to the flange 136. A housing 178 is operatively connected tothe flange 136 and defines a cavity 180 in which the plate 146 islocated. The plate 146 moves along the direction 150 within the cavity180 and is supported for longitudinal movement along each of the shafts170. While four (4) of the shafts or rods 170 are illustrated, othernumbers of shafts or rods are contemplated.

As previously described, the actuator 156 engages the plate 146 toadjust the position of the plate with respect to the transmission flange136 toward and away from the final drive assembly 108. While oneactuator 156 is illustrated, in other embodiments, more than oneactuator is contemplated. In one embodiment, the housing 178 is removedfrom the flange 136 to adjust the position of the plate 146. In anotherembodiment, the housing 178 includes an access hole or aperture (notshown) appropriately located to enable access to the actuator 156.

FIG. 5 illustrates another embodiment of the connect/disconnectmechanism or transmission coupler 130. In this embodiment, the actuator156 includes a motor drive 182 operatively connected to the actuator 156of the worm drive mechanism 154 to move the plate 146 along thedirection 150. The motor drive 182 includes a motor operativelyconnected to a power source (not shown) which provides sufficientcurrent and voltage to move the splines 152 into and out of engagementwith the splines 142. The source of power includes a power controlfeature, such as a switch, which provides power to the motor drive 182when needed. In another embodiment, the power control feature includes acontroller operatively connected to the motor drive 182. The controllerresponds to user inputs provided by a user, such as a technician,through a user interface including buttons, switches, and touch screens.

In other embodiments, the actuator 156 is controlled by an electric ACor DC motor, a hydraulic motor, or any type of motor. Alternatively, atool or mechanism such as a socket wrench or the like may be able tocouple to the knob 164 of FIGS. 2 and 3 to rotatably drive the actuator156. In further embodiments, automatic, semi-automatic, or non-automaticmechanisms for driving the actuator 156 are contemplated. Some of thesemechanisms can be electrically-powered, mechanically-powered,hydraulically-powered, pneumatically-powered, or a combination thereof.

FIGS. 6-10 illustrate a further embodiment of a transmission 200including a transmission output shaft 202 configured to drive a finaldrive assembly 204 to drive the drive track 112 of FIG. 1 or otherground engaging mechanism of the vehicle or machine 100. In FIG. 6, thetransmission output shaft 202 is disconnected from the final driveassembly 204. See also FIGS. 8-10 illustrating end views of thetransmission 200.

The drive assembly 204 includes a connector 206 having splines 208configured to engage an engagement structure, such as splines 210, of amovable connector 212. In the illustrated embodiment, the movableconnector 212 includes a shaft moving along a direction 214 to engagewith and to disengage from the connector 206.

A connect/disconnect mechanism or transmission coupler 220 is configuredto move the moveable connector 212 from a disconnected position shown inFIG. 6 to a connected position with the drive assembly shown in FIG. 7.The connect/disconnect mechanism 220 includes a flange or collar 222coupled to a transmission housing 224 of the transmission 200. Thecollar 222 is fixedly coupled to the housing 224 by one or moreconnectors 226. The collar 222 includes a cavity or space 228 defining apocket arranged to hold an actuator or worm drive 230 including a wormgear 232. The worm gear 232 engages a coupling shaft, such as a wormwheel 234, further illustrated in FIG. 9 and FIG. 10.

The worm drive 230 is fixed within the space 228 by a retainer orretaining ring 235 fixedly coupled to the collar 222 by one or moreconnectors 236. The retainer 235 is generally cylindrical and surroundsthe output shaft 202. The worm gear 232 includes an actuator or driver238 that extends from the worm gear 232 and includes an input interface240 configured to accept a tool that applies a torque to the driver 238.In one embodiment, the tool is a hand tool, either powered or unpowered,and manipulated by an individual, such as an operator or maintenanceperson. In another embodiment, the tool is a motor or motor drivecontrolled by a switch located at or in the vehicle. The application ofa torque to the input interface rotates the worm gear 232 about arotational axis inclined with respect to the direction 214. In oneembodiment, the rotational axis of the worm gear 232 is substantiallyparallel to the direction 214. Other inclinations of the rotational axisof the worm gear 232 with respect to the direction 214 are contemplated.

The worm wheel 234 engages and drives an internal lead screw 242 about arotational axis defined by an axial center 243 of the output shaft. Theworm wheel 234 includes a keyway 244 (see FIGS. 8-10) defining a cavityfor a key 246 (see FIG. 10). The key 246 engages a cavity or slot (notshown) in the internal lead screw 242. As the worm drive 230 drives theworm wheel 234 about the rotational axis 243, the worm wheel 234 drivesthe internal lead screw 242 to rotate about the axis 243. The internallead screw 242 surrounds and is centered about the axis 243 and drivesan external lead screw 248.

A ball bearing 250 is located in a cavity adjacent to the external leadscrew 248 and is held in the cavity by a retainer 252. Locatedadjacently to the ball bearing 250 is a compression spring 254 whichabuts the ball bearing 250 and the moveable connector 212. As theexternal lead screw 248 moves from the location illustrated in FIG. 6 tothe location of FIG. 7, the spring 254 moves or drives the moveableconnector 212 in response to the movement of the external lead screw248. The moveable connector 212 is moved toward the drive assembly 206to engage the transmission output shaft 202 with the final driveassembly 204. The moveable connector 212 is moved away from the driveassembly to disengage the transmission output shaft away from the finaldrive assembly.

The spring 254 is compression spring configured to aid in the alignmentof the splines 210 with the splines 208. If for instance, the splines210 are not properly aligned with the splines 208, the ends of each ofthe splines 210 and 208 engage one another and can prevent furthermovement of the moveable connector 212 toward the drive assembly 206,thereby preventing engagement of the transmission output shaft 202 withthe final drive assembly 204. As a result, when the moveable connector212 moves toward the drive assembly 206, the spring is compressed andprovides a resisting force that is apparent to an individual or to amotor drive adjusting the worm drive 230. When this event occurs, themoveable connector 212 is rotated by the operator or motor drive aboutits axis to align the splines 210 with the splines 208. Once properlyaligned, the moveable connector 212 is moved to substantially or tofully engage the splines 210 with the splines 208.

The transmission coupler 220 further includes one or more pins 256 whichare configured to substantially prevent rotation of the external leadscrew 248 during movement of the connector 212 toward or away from thedrive assembly 206. One end of the one or more pins 256 is pressed intoan aperture formed in the collar 222 or the housing 224 or both. Theother end extends into an aperture of the external lead screw 248. Theaperture provides a sliding fit to the pin 256 such that the externallead screw 248 travels axially along the direction 214, while preventingthe lead screw 248 from rotating with respect to the internal lead screw242. Other embodiments are contemplated that do not include the pin(s)256 or include other mechanisms to substantially prevent rotation of theexternal lead screw 248 with respect to the internal lead screw 242.

In one or more embodiments, a spring loaded locking mechanism 260 isconfigured to substantially prevent unintended disengagement of thetransmission 200 from the final drive assembly 204. As seen in FIG. 8,the actuator 238 is spring biased by a spring 262 located about a stemof the actuator 238 and is held in place by a plate 264. The plate 264includes an aperture in its inner dimension to engage a hex shaped inputinterface 240 and to prevent the interface 240 from being moved. A keyon the outer diameter of the plate 264 engages a slot in the housing andthe spring 262 holds the plate in engagement with the hex shaped head ofinput interface 240. In this position, the actuator 238 is preventedfrom being rotated which prevents disengagement of the transmission 200from the final drive assembly 204. To disconnect the output of thetransmission from the final drive 204, a tool engages the hex shapedinterface and the plate 264 is pushed to the left as illustrated atposition 266. As the tool engages the interface, the plate 264compresses the spring 262. Once the tool sufficiently engages theinterface, the plate 264 is disengaged from the hex shaped interface toenable the tool to rotate the actuator 238. Rotation of the actuatordisengages the output of the transmission 200 from the final driveassembly 204. Other configurations of the actuator 240 and the actuatorreceiving hole in the plate 264 are contemplated.

While exemplary embodiments incorporating the principles of the presentinvention have been disclosed hereinabove, the present invention is notlimited to the disclosed embodiments. Instead, this application isintended to cover any variations, uses, or adaptations of the inventionusing its general principles. Further, this application is intended tocover such departures from the present disclosure as come within knownor customary practice in the art to which this invention pertains andwhich fall within the limits of the appended claims.

What is claimed is:
 1. A vehicle drivetrain including a transmissionconfigured to move a vehicle having a surface engaging traction member,the vehicle drivetrain comprising: a final drive assembly configured todrive the surface engaging traction member; a transmission couplerincluding a plate having one or more channels, a transmission connectoroperatively connected to the plate, and one or more shafts eachcorrespondingly located in and slidingly engaging one of the channels,the one or more shafts fixedly coupled to the transmission and disposedbetween the transmission and the final drive assembly, wherein the plateof the transmission coupler slides along the one or more shafts from afirst position in which the transmission connector is engaged with thefinal drive assembly and to a second position in which the transmissionconnector is disengaged from the final drive assembly; and an actuator,operatively connected to the transmission coupler, configured to movethe transmission coupler between the first position and the secondposition.
 2. The vehicle drivetrain of claim 1 wherein the actuator isconfigured to move the transmission connector of the transmissioncoupler along a longitudinal axis of the transmission.
 3. The vehicledrivetrain of claim 2 wherein the actuator includes an actuator shaftinclined with respect to the longitudinal axis of the transmission. 4.The vehicle drivetrain of claim 3 wherein the actuator includes a wormdrive mechanism.
 5. The vehicle drivetrain of claim 3 wherein theactuator includes a motor drive.
 6. The vehicle drivetrain of claim 1wherein sliding movement of the plate moves the transmission connectorto engage a drive assembly coupler of the final drive assembly.
 7. Thevehicle drivetrain of claim 6 wherein the transmission coupler comprisesa coupling shaft operatively connected to the actuator, wherein theactuator moves the coupling shaft along a direction toward and away fromthe drive assembly coupler.
 8. The vehicle drivetrain of claim 7 whereinthe transmission connector includes an engagement structure includingsplines.
 9. The vehicle drivetrain of claim 8 wherein the coupling shaftis configured to move in a direction between the transmission and thedrive assembly coupler, and the actuator is arranged in a directioninclined with respect to the moving direction.
 10. The vehicledrivetrain of claim 9 wherein the actuator comprises a worm driveoperatively connected to the coupling shaft, wherein actuation of theworm drive moves the coupling shaft in the direction toward and awayfrom the drive assembly coupler.
 11. A method for disconnecting andconnecting a transmission drive element of a transmission from a finaldrive assembly, the method comprising: slidingly moving a transmissionconnector along the transmission drive element with a plate, the platedefining at least one channel and being disposed in proximity of thetransmission drive element, by slidingly moving the plate along at leastone shaft, wherein the at least one shaft is supported by a flangecoupled to the transmission, the at least one shaft being located in acorresponding at least one channel, the plate slidingly moving away fromthe transmission and toward the final drive assembly to engage a driveassembly connector with the transmission connector; and disengaging thetransmission connector from the drive assembly connector by slidinglymoving the plate along the at least one shaft and away from the driveassembly connector, wherein the transmission connector slidingly movesalong a path defined by a longitudinal axis of the transmission driveelement away from the drive assembly connector for disengaging thetransmission drive element from the final drive assembly.
 12. The methodof claim 11 wherein the slidingly moving the transmission connectorincludes sliding the transmission connector away from the transmissionon the transmission drive element of the transmission.
 13. The method ofclaim 11 wherein the slidingly moving the transmission connectorincludes rotating a rotatable drive actuator to move the transmissionconnector from a first position in which the transmission connector isdisengaged from the final drive assembly to a second position in whichthe transmission connector is engaged with the final drive assembly. 14.The method of claim 13 wherein the slidingly moving the transmissionconnector includes rotating the rotatable drive actuator to move thetransmission connector along a path defined by a longitudinal axis ofthe transmission drive element.
 15. The method of claim 14 wherein therotatable drive actuator includes a knob configured to engage a tool.16. The method of claim 14 further comprising rotating the rotatabledrive actuator about an axis inclined with respect to the path definedby the longitudinal axis of the transmission drive element.
 17. Themethod of claim 16 further comprising rotating the rotatable driveactuator with a motor drive.
 18. The method of claim 11 wherein theslidingly moving the transmission connector includes slidingly movingsplines of the transmission connector into contact with splines of thedrive assembly connector to engage the transmission drive element withthe final drive assembly.
 19. A method for disconnecting and connectinga transmission drive element of a transmission from a final driveassembly, the method comprising: slidingly moving a transmissionconnector along the transmission drive element with a plate, the platedefining at least one channel and being disposed in proximity of thetransmission drive element, by slidingly moving the plate along at leastone shaft, the at least one shaft being located in a corresponding atleast one channel, the plate slidingly moving away from the transmissionand toward the final drive assembly to engage a drive assembly connectorwith the transmission connector; and disengaging the transmissionconnector from the drive assembly connector by slidingly moving theplate along the at least one shaft and away from the drive assemblyconnector, wherein the transmission connector slidingly moves along apath defined by a longitudinal axis of the transmission drive elementaway from the drive assembly connector for disengaging the transmissiondrive element from the final drive assembly; wherein the slidinglymoving the transmission connector includes slidingly moving splines ofthe transmission connector into contact with splines of the driveassembly connector to engage the transmission drive element with thefinal drive assembly; wherein the slidingly moving the transmissionconnector includes fixedly connecting the plate with the transmissionconnector to move the transmission connector in response to movement ofthe plate; and wherein the at least one shaft is supported by a flangecoupled to the transmission.